Researchers at the University of Ottawa have found that using helical light beams in disordered solids reveals a phenomenon known as dichroism, which is differential absorption of light. This discovery contradicts prior beliefs and provides an opportunity to alter the way light interacts with these materials by changing the properties of the light itself. These findings also underscore the importance of short-to-medium-range order within disordered solids in influencing how materials react to light.
Led by , who is a Department of Physics researcher who heads 91精品黑料吃瓜鈥檚 research group, and doctoral students Ashish Jain and Jean-Luc Begin, this year-long study was conducted in collaboration with professors and at 91精品黑料吃瓜鈥檚 .
鈥淭he research was conducted by employing helical light beams carrying orbital angular momentum to probe the optical properties of amorphous and crystalline materials,鈥 explains Professor Bhardwaj. 鈥淏y utilizing a birefringent liquid crystal plate, called a q-plate, developed by Professor Karimi鈥檚 group, we were able to produce designer light fields with twisted wavefronts that describe a corkscrew pattern.鈥
鈥淥ur team developed a new method to show that non-crystalline solids can exhibit helical dichroism鈥
Ravi Bhardwaj
鈥 Full Professor, Department of Physics
This research has broad implications and challenges current beliefs about the optical characteristics of amorphous solids. It also presents opportunities to control a material鈥檚 optical behaviour by using helical light beams. These findings are significant for multiple fields, including materials science, optics, and chiroptical spectroscopy.
鈥淥ur team developed a new method to show that non-crystalline solids can exhibit helical dichroism, which means they react differently to light that twists in different directions,鈥 says Professor Bhardwaj. 鈥淭he experimental evidence was complemented by theoretical models developed in collaboration with Professor Brabec, providing a comprehensive understanding of the observed phenomena.鈥
鈥淭he helical light served as an indirect probe of short-to-medium-range order in disordered solids that extends up to 2 nm. Our research will aid efforts to understand the mysterious nature of amorphous materials,鈥 adds Ashish Jain and Jean-Luc B茅gin.
This work significantly advances our understanding of the optical properties of solid-state materials. By demonstrating the existence of intrinsic dichroism in both crystalline and amorphous solids, this research paves the way for innovative applications and further exploration of the unique capabilities of helical light beams in probing and manipulating material properties.
The study, titled 鈥溾, was published in Nature Communications.